Preface

	"A journey of a thousand miles begins with a single step."
	--Laozi (604 BC - 531 BC)

Data science is a relatively new knowledge domain that requires the successful integration of linear algebra, statistical modelling, visualization, computational linguistics, graph analysis, machine learning, business intelligence, and data storage and retrieval.

The Python programming language, having conquered the scientific community during the last decade, is now an indispensable tool for the data science practitioner and a must-have tool for every aspiring data scientist. Python will offer you a fast, reliable, cross-platform, mature environment for data analysis, machine learning, and algorithmic problem solving. Whatever stopped you before from mastering Python for data science applications will be easily overcome by our easy step-by-step and example-oriented approach that will help you apply the most straightforward and effective Python tools to both demonstrative and real-world datasets.

Leveraging your existing knowledge of Python syntax and constructs (but don't worry, we have some Python tutorials if you need to acquire more knowledge on the language), this book will start by introducing you to the process of setting up your essential data science toolbox. Then, it will guide you through all the data munging and preprocessing phases. A necessary amount of time will be spent in explaining the core activities related to transforming, fixing, exploring, and processing data. Then, we will demonstrate advanced data science operations in order to enhance critical information, set up an experimental pipeline for variable and hypothesis selection, optimize hyper-parameters, and use cross-validation and testing in an effective way.

Finally, we will complete the overview by presenting you with the main machine learning algorithms, graph analysis technicalities, and all the visualization instruments that can make your life easier when it comes to presenting your results.

In this walkthrough, which is structured as a data science project, you will always be accompanied by clear code and simplified examples to help you understand the underlying mechanics and real-world datasets. It will also give you hints dictated by experience to help you immediately operate on your current projects. Are you ready to start? We are sure that you are ready to take the first step towards a long and incredibly rewarding journey.